• Journal of Korea Society of Digital Industry and Information Management
• /
• v.7 no.2
• /
• pp.47-58
• /
• 2011

Snoop was suitably designed for wired and wireless network as having snoop agent module in BS(Base Station) which is connecting to both wired and wireless network in order to supplement the problems of TCP. This study examined performance difference by using the web traffic taken wide possession in current internet traffic. The web traffic has greater amount of traffic, shorter life time, and smaller size than other traffics. This study found that snoop producing performance improvement of wireless network in the network mixed with the wired and wireless lead performance loss when transmitting web traffic. This study found that in case of web traffic is transmitted it bring a performance improvement of web traffic as computing BWE((Bandwidth Expansion), and also found that this study prove of performance improvement by decreasing local retranmission.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.16 no.8
• /
• pp.2627-2647
• /
• 2022

The easy scalability and low cost of range-free localization algorithms have led to their wide attention and application in node localization of wireless sensor networks. However, the existing range-free localization algorithms still have problems, such as large cumulative errors and poor localization performance. To solve these problems, an incremental strategy-based residual regression network is proposed for node localization in wireless sensor networks. The algorithm predicts the coordinates of the nodes to be solved by building a deep learning model and fine-tunes the prediction results by regression based on the intersection of the communication range between the predicted and real coordinates and the loss function, which improves the localization performance of the algorithm. Moreover, a correction scheme is proposed to correct the augmented data in the incremental strategy, which reduces the cumulative error generated during the algorithm localization. The analysis through simulation experiments demonstrates that our proposed algorithm has strong robustness and has obvious advantages in localization performance compared with other algorithms.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.9 no.3
• /
• pp.91-98
• /
• 2013

Node which plays the role of cache server does not exist in the wireless ad-hoc network consisting of only mobile nodes. Even if it exists, it is difficult to provide cache services due to the movement of nodes. Therefore, the cooperative cache technique is necessary in order to improve the efficiency of information access by reducing data access time and use of bandwidth in the wireless ad-hoc network. In this paper, the whole network is divided into zones which don't overlap and master node of each zone is elected. General node of each zone has ZICT and manages cache data to cooperative cache and gateway node use NZCT to manage cache information of neighbor zone. We proposed security structure which can accomplish send and receive in the only node issued id key in the elected master node in order to prepare for cache consistent attack which is vulnerability of distributed caching techniques. The performance of the proposed method in this paper could confirm the excellent performance through comparative experiments of GCC and GC techniques.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.6 no.3
• /
• pp.31-36
• /
• 2010

In this paper, We propose a transaction signing-based authentication scheme for protecting sinkhole attacks in wireless sensor networks. Sinkhole attack makes packets that flow network pass through attacker. So, Sinkhole attack can be extended to various kind of attacks such as denial of service attacks, selective delivery or data tamper etc. We analyze sinkhole attack methods in directed diffusion based wireless sensor networks. For the purpose of response to attack method, Transaction signing-based authentication scheme is proposed. This scheme can work for those sensor networks which use directed diffusion based wireless sensor networks. The validity of proposed scheme is provided by BAN logic.

• Journal of the Korean Society of Industry Convergence
• /
• v.26 no.5
• /
• pp.867-874
• /
• 2023

In this paper, a wireless communication-based sensor data monitoring device with an explosion-proof (Exd IIC) case was implemented to enable installation at explosion-risk industrial sites such as plants. In existing industrial plant sites, most of the temperature sensors and vibration and impact sensors are wired up to several kilometers, which takes a lot of time and money to bury long pipes and cables. In addition, there are not many cases where some wireless devices have been applied to actual plant industry sites due to communication quality problems. Therefore, in order to solve this problem, zigbee mesh wireless communication was applied to provide high reliability wireless communication quality to industrial plant sites, and the time and cost incurred in new or additional installation of sensors could be greatly reduced. In particular, in the event of loss or error of some wireless communication devices, the communication network is automatically bypassed or recovered to enable real-time data monitoring.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.4 no.4
• /
• pp.1-8
• /
• 2008

The USN is important in technique, unmanned observation using wireless network camera, detection technique that use intrusion detection sensor. But these encrypted data transmission and processing technique through sensor network, method of the staff's location recognition and arrangement aren't serviced still as a integrated system in facility security industry. This paper proposed that improve facility management, the staff present recognition and system efficiency using RFID, USN and wireless camera.

• Journal of the Korean Society of Industry Convergence
• /
• v.4 no.4
• /
• pp.441-450
• /
• 2001

This dissertation deal with over-all wireless communication technology. And introduce wireless communication technology analytically that it use for Home-LAN communication technology (HomeRF, Bluetooth, IEEE 802.11, HIPERLAN, etc). Home-LAN communications issue by the terminal field of the latest high-speed network construction. This technologies possesses characteristics and significances as the representative technology using in Home-LAN communication technology. Also, the method of application is conditional on individually. Wireless LAN put Home-LAN communications to practical use. Bluetooth have practical use for an individual mobile communications with internet. HomeRF have a vision that the construction of wireless system in house purely. Therefore, this dissertation investigates merits and demerits between those technologies. And then leads the most compatible technology for application of Home-LAN. Finally, this thesis have a view of the development course hereafter.

• Journal of the Korean Society of Industry Convergence
• /
• v.8 no.2
• /
• pp.97-104
• /
• 2005

Usually, propagation attenuation of millimeter wave occurs by rainfall, snowfall, temperature, effect of pressure of air. In 60GHz wave band wireless communication network, temperature change becomes big factor of propagation loss department. Also, temperature change causes disturbance of 60GHz frequency at transceiver. In this study, we used 60GHz transceiver and found propagation loss of wireless path and operating frequency disturbance characteristics. In transceiver that there is no temperature compensated device, operating frequency of TX changed by 60.865GHz at temperature of $-5^{\circ}C$, and appeared by 60.730GHz when is $50^{\circ}C$. Therefore, operating frequency change width by temperature change are about 100MHz, greatly. But, in transceiver that there is temperature compensated device, operating frequency of TX changed by 60.830GHz at temperature of $-5^{\circ}C$, and appeared by 60.710GHz when is $50^{\circ}C$. Therefore, operating frequency change width by temperature change are about 20MHz. According to these result, we constructed between buildings examination wireless site for point to point wireless communication using 60GHz band transceivers who have do temperature compensated device, and investigated data transmission characteristics about ambient temperature change. Therefore, if use transceiver that have temperature compensated device, may overcome the wireless transmission error in 60GHz band wireless communication LAN networks despite of ambient temperature change.

• Journal of the Korean Society of Industry Convergence
• /
• v.25 no.2_2
• /
• pp.299-307
• /
• 2022

Wireless earphones, along with smart devices, are the most sought-after products by consumers. Compared to general earphones, wireless earphones do not have twisted wires and are easy to use, so various types of products are currently on the market. However, information on quality is somewhat lacking, so consumers tend to purchase products according to brand awareness, and manufacturers are delivering information to consumers using different standards for each product because there is no standard for quality control. In particular, the playback time of wireless earphones is a factor that directly affects consumers' purchases, so a standard measurement method is needed to properly measure it. In this paper, we present a method for measuring the audio playback time of wireless earphones derived from domestic wireless earphone status survey, commercial product measurement test, and research analysis, and a developed standard measurement method. In addition, this paper proposes a measurement result reporting format to provide accurate information to consumers and induce a fair competitive environment for each product to manufacturers.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
• /
• v.26 no.8
• /
• pp.699-709
• /
• 2015

The role of wireless power transmission(WPT) on the information communication technology and the re-set location of WPT technology in the hype cycle to apply the recent trend of market and industry are presented in this paper. We describe the need of national strategy to change from the phase of industry promote to the phase of industry revitalization. The relation between the management of spectrum and electromagnetic environment is analysed in the view point of physics. We also propose the direction of policy for industry revitalization adapted the world changing circumstance.